Endohydrolysis of (1->6)-beta-D-galactosidic linkages in arabinogalactan proteins and (1->3):(1->6)-beta-galactans to yield galactose and (1->6)-beta-galactobiose as the final products

Comment

The enzyme specifically hydrolyses 1,6-beta-D-galactooligosaccharides with a degree of polymerization (DP) higher than 3, and their acidic derivatives with 4-O-methylglucosyluronate or glucosyluronate groups at the non-reducing terminals [2]. 1,3-beta-D- and 1,4-beta-D-galactosyl residues cannot act as substrates. The enzyme can also hydrolyse alpha-L-arabinofuranosidase-treated arabinogalactan protein (AGP) extracted from radish roots [2,3]. AGPs are thought to be involved in many physiological events, such as cell division, cell expansion and cell death [3].